The present invention relates to a cell culture flask.
It is common, within the field of cell biology, to culture cells in order to harvest biologically active compounds produced by the cells, or indeed the cells themselves. Such cells are generally cultured on static plates which may be enclosed in a bottle or flask or on a plate with a cooperating lid. Flasks may generally be accessed through a neck portion, closed by means of a cap. Plates are accessed by the removal of a lid portion. Both flasks and plates are , in use, laid on their side, so that the maximum possible surface are a is horizontal. The cell cultivating medium covers the inner surface area of the flask wall. Hereafter in this specification plates and flasks are collectively referred to as flasks. Over time, the industry has developed a number of sizes of flask that are considered to be standard. One of these, known as the T-flask, has four orthogonal walls (two major walls and two minor walls) and is configured so that the maximum surface are a is available to the cells when the flask is laid on one of its major sides.
In order to make maximum use of the volume enclosed by such a flask it has been suggested that the flask could be divided by a number of internal walls. For example, U.S. Pat. No. 5,310,676 discloses a cell culturing flask comprising superposed, separate partition wall members forming mutually spaced partition walls, which define three superposed chambers for containing a cell cultivating medium therebetween. The superposed partition wall members each comprise a partition wall and an upstanding peripheral wall extending transversely thereto in order to provide a fluid passage which allows the cell culture to be distributed between the various levels within the device.
It is also known within the art that certain cell cultures will only thrive between certain concentration limits. If the concentration of cells and cell culture medium is too low, ie the are a on which the cell culture medium is isolated is too large, then the cells will not thrive. Conversely, when the cell population increases beyond a certain level further growth cannot be sustained within the limits of the are a on which the cells are isolated. Therefore, it would be advantageous for the cells to be moved from one surface to a second larger surface and possibly subsequent further larger surfaces within the culture flask during the culturing process in order to maximise culture growth without decanting the medium cell suspension from one flask into one or more others.